1. Field of the Invention
The present invention relates to a remote control transmission apparatus equipped with a learning function which is adapted to store control data for controlled devices of other remote control transmission apparatus and retransmit thereto the stored control data.
2. Description of the Prior Art
In general, a TV receiver, a VTR, a laser disc and similar audiovisuals are provided with remote control transmission apparatus for remote control of their operations. This remote control requires a different remote control transmission apparatus for each audiovisual. Hence, it takes much time to determine which remote control apparatus to use in case the number of audiovisuals involved is large. The remote operation of all the audiovisuals through the use of the same remote control transmission apparatus, if possible, would provide enhanced operability of remote control. From this point of view, there has been developed a remote control transmission apparatus with a learning function which is adapted to store control data of controlled devices of a plurality of remote control transmission apparatus and retransmit thereto the stored control data.
With reference to FIGS. 10 and 11, the conventional remote control transmission apparatus equipped with a learning function, identified generally by 100, will be described. The remote control transmission apparatus 100 stores and retransmit control data of remote control transmission apparatus (hereinafter referred to as remote control transmitters) A, B, C, . . . which are used for remote operation of different audiovisuals. For example, in the case of storing control data of the remote control transmitter A, its transmitting side is directed toward the receiving side of the remote control transmission apparatus 100(refer to FIG. 11), and a mode selection switch 107 of the latter is set at a learning side. Then, by depressing a key KA1 of the remote control transmitter A from which is sent control data d (for example, to switch on a TV receiver which is a controlled device) to be stored is pressed, and at the same time, depressing a key k1 arbitrarily selected from a key matrix 101 of the remote control transmission apparatus 100 is pressed, by which the control data d is stored in correspondence with the pressed key k1.
That is, upon depression of the key KA1, a remote control signal containing the control data d is sent from the remote control transmitter A to the remote control transmission apparatus 100, wherein it is received by a photodiode, thereafter being amplified and wave-shaped and being fed into a demodulation part 103. The demodulation part 103 detects from the remote control signal its transmission format f and the control data d, and provides them to a microprocessor 104. The microprocessor 104 is connected to the key matrix 101 so that, upon depression of any one of the keys in the key matrix 101, the key code of the depressed key is input into the microprocessor 104. Assuming that the key k1 is already depressed when the control data d is input into the microprocessor 104 from the demodulation part 103 as mentioned above, the transmission format f and the control data d are stored in a RAM 105 at the address corresponding to the key code of the key k1. In a ROM 106 connected to the microprocessor 104 there are stored programs for its operation.
Setting the mode selection switch 107 to the transmitting side after the learning operation and depressing, for example, the key k1, its key code is provided from the key matrix 101 to the microprocessor 104. When the mode selection switch 107 is held at the transmitting side, the microprocessor 104 reads out the transmission format f and the control data d stored in the RAM 105 at the address corresponding to the key code of the key k1, and provides them to an output circuit 108. Based on transmission data generated from the transmission format f and the control data d, the output circuit 108 drives a driving transistor 110 connected to a light emitting diode 109, from which is transmitted a remote control signal containing the control data d and having the same transmission format as that used by the remote control transmitter A.
By simultaneous depression of any one of the keys KA1, KA2, . . . of the remote control transmitter A and an arbitrary one of the keys k1, k2, . . . of the key matrix 101 on the remote control transmission apparatus 100 as described above, control data transmitted by the depression of the key of the remote control transmitter A is stored in correspondence to the key depressed on the remote control transmission apparatus 100. The same holds true with regard to the other remote control transmitters B, C, . . . for remote operation of other audiovisuals. Thus, the single remote control transmission apparatus 100 can be used for remote control of a plurality of audiovisuals irrespective of their categories, makers and so forth.
In such a remote control transmission apparatus 100 with a learning function, however, it is necessary that keys corresponding to all keys of the remote control transmitters A, B, C, . . . to be learned be disposed on the operating panel--this imposes limitations on the design of the operating panel and impairs its usability because it is cumbersome to search a number of keys for a desired one to operate.
The contents and kinds of the control data to be stored vary with the categories or makers of the devices to be controlled. It is impossible to predetermine the number of keys and their arrangement on the remote control transmission apparatus 100 to accommodate such a variety of control data. It is conventional to store the control data in a one-to-one correspondence with user's arbitrarily selected keys on the remote control transmission apparatus 100. However, the learning operation, which is common to all the keys, makes unclear the correspondence between the keys and the stored control data--this incurs the possibility of even the depression of a desired key resulting in erroneous activation of an unintended device different from the desired one or erroneous execution of an unintended operation.
Conventionally, users affix to all the keys labels bearing indications of the learned contents of control data, but affixing such labels to all the keys concerned is troublesome and time-consuming.
When plural pieces of control data are stored in association with each key with a view to avoid an increase in the number of keys on the operating panel, it is difficult to indicate all the contents of the control data involved on the label because of limited space on the operating panel.